Zhang Zhongjing is from Gedong, Nanyang. Treatise on Febrile Diseases, written by him, is a masterpiece of doctors and is regarded as a classic by doctors in past dynasties. Zhang Zhongjing has a famous saying: "if you advance, you will survive;" If you retreat, you will save the people; " You can't be a good doctor and you can't be a good doctor. "When the Eastern Han Dynasty was the magistrate of Changsha, he visited the sick and took medicine and practiced medicine in the lobby. Later, he resolutely resigned and went back to his hometown to treat his neighbors. When he got home, it was already winter. He saw that the villagers on both sides of the Baihe River were sallow and emaciated, hungry and cold, and many people's ears were frozen. He asked his disciples to build a medical shed and a cauldron in Dongguan, Nanyang, and to give up "Quhan Joule Decoction" to treat chilblain on the day of winter solstice. He boiled mutton, pepper and some herbs for dispelling cold in a pot, then took out mutton and medicine and chopped them up, making ear-shaped dumplings with bread. After cooking, he distributed two horns and a big bowl of broth to everyone who came to ask for medicine. People ate "Joule" and drank "Quhan Decoction", and they were all hot, their ears were hot, and their frostbitten ears were cured. Later generations learned the appearance of Joule and packaged it into food, also called "jiaozi" or "flat food".
When you eat jiaozi on the solstice in winter, you will never forget the kindness of Zhang Zhongjing, a "medical sage", in "Quhan Joule Decoction". Up to now, there is still a folk song in Nanyang, which is called "jiaozi Bowl, and nobody cares about frozen ears." .